Topical linezolid for refractory bilateral Mycobacterium chelonae post-laser-assisted in situ keratomileusis keratitis.

Abstract

diagnosis; (2) successful combination of topical, oral, and intraocular therapy with drugs that can reach therapeutic levels in aqueous and vitreous and are effective in vivo for other Acanthamoeba infections; and (3) guiding treatment by effective monitoring of the response by Acanthamoeba. We think oral and topical administration of voriconazole must have achieved a sustained therapeutic dose and frequent administration of intraocular voriconazole produced high peak levels, increasing effectiveness. Topical chlorhexidine was used before the PK but the keratitis worsened, raising the question of its effectiveness in our patient. It is unknown whether topical chlorhexidine can reach aqueous therapeutic levels; however, rabbit studies have shown that frequent instillation of chlorhexidine, 0.02%, in epithelialized corneas produces concentrations 10 to 40 times lower than voriconazole but, in our experience, a similar 90% inhibitory concentration. Moreover, in the other described cases, topical antiseptics such as chlorhexidine used after PK did not prevent endophthalmitis. Therefore, we believe chlorhexidine did not play a major role in our case. The susceptibility of Acanthamoeba to trimethoprim/sulfamethoxazole, also used in our patient, is based on a few reports; we have not tested the susceptibility of the patient’s strain and cannot be sure of its real contribution.